1. Field of the Invention
The present invention relates to a design/production technique for micro/nano-devices such as a semiconductor device, MEMS (micro electro mechanical system) device, HDD (hard disk drive) head, et cetera, and in particular to a three-dimensional device simulation program product and a three-dimensional device simulation system for generating a three-dimensional feature model required for a performance simulation of a device, for example.
2. Description of the Related Art
There is a disclosed conventional technique capable of importing a feature pattern that is imaged for each production process, generating a layer image by adding characteristic data of each production process to the feature pattern, acquiring a feature correlation from image data and mask pattern data which are imported in each production process, and simulating a feature at the time of producing from a mask pattern feature by using the correlation information (e.g., refer to Laid-Open Japanese Patent Application Publication No. 10-41366).
There is also a disclosed conventional technique for generating a three-dimensional feature by adding a conversion of the height direction to two-dimensional mask data and by further adding a conversion by using knowledge information reflecting a structure. Thereby generating a correct three-dimensional feature allowing an accurate extraction of parameters for performing a characteristic simulation of a semiconductor device from two-dimensional mask data in a three-dimensional feature generation method for generating three-dimensional feature data by using mask data that is two-dimensional data (e.g., refer to Laid-Open Japanese Patent Application Publication No. 2000-207433).
There is also a disclosed conventional technique for changing an optical intensity simulation model according to a mask pattern feature and a positional relationship of mask patterns, and performing an optical proximity effect correction (OPC) of a simulation base by changing the number of repetition of the optical intensity simulation, thereby making it possible to perform the OPCs for all mask patterns within a chip and suppress an increase of time length required for the OPC (e.g., refer to Laid-Open Japanese Patent Application Publication No. 2001-174974).
In recent years, the progress decreasing device size has placed an increased importance in a device's performance simulation by a computer. However, generation of a three-dimensional feature model for a simulation requires a very large amount of work time. For example, three-dimensional models are sometimes manually generated by using a mechanical three-dimensional computer aided design (CAD) program. Wherein a complex device may require several hours to generate the model.
As another model generation technique, a method exists for generating a three-dimensional feature of a device by using a simulator for a production process. This method simulates a production process such as etching, sputtering, et cetera, thereby calculating a device feature in detail. This method, however, only allows a partial modeling because of the difficulty of performing an accurate simulation, and because it takes several hours just to calculate a narrow area.
Although there is a method for performing a three-dimensional simulation of an entire device in a MEMS-use simulation system, the method is only capable of generating a simple three-dimensional model. Hence, it is capable of handling only a simple feature in a MEM device.
FIG. 1 is a drawing that depicts a conventional technique.
The conventional MEMS-use simulation system is used for generating a model of a simple three-dimensional feature as shown in FIG. 1 (B) by ejecting a simple featured mask as shown by FIG. 1 (A).
Other examples relating to modeling of a device include an offset method and a level set method; both of which are techniques mainly used for process simulation.
In comparison, three-dimensional features are becoming increasingly complex, large scaled and multi-layered while devices are decreasing in size. Therefore, the demand for more effective methods for generating three-dimensional feature models is increasing.